Sterilizing medicinal pellets or the like



Sept. 21, 1943. R. E. MULLl-GAN STERILIZ ING MEDICINAL PELLETS OR THE LIKE Filed Feb. 2, 1942 Patented Sept. 21,194:

s'raarmzmc MED 'rna roman runners on LIK Robert E. Mulligan, East St. Louis, 111., assignor to The Blue Line Chemical 00., St. Louis, Mo.,

a corporation of Missouri [ap lication February a, 1942, Serial No. 429,170

' 11 Claims. (01. 21-2) My invention relates" to the sterilization of medicinal pellets, particularly to the sterilization of pellets unable to withstand the high temperatures necessary ,i'or sterilization by heat;

Specifically, the invention relates to the sterilization of a potentthermolabile drug for subcutaneous implantation in human subjects, such as diethylstilbestrol dipropionate. This and other drugs melt or deteriorate at around 106 to 107 degrees centigrade, whereas. a temperature. about that high is required to produce sterilization. Attempts toaccomplish sterilization by interformaldehyde is placed a pledget I of hospital cotton or like fluiiy, open material. On this pledget 3 is placed a pellet l of diethylstilbestrol dipropionate, say of about one-hundred millirams in weight. Near the top of the test tube is placed a second cotton pledget and the glass .tube is heated and constricted as at 8 to leave only a very small opening above the upper pledget 5.

a plurality e the fllled test tubes l are-placed in a rack 'l or other suitable support which is then placed in a suitable oven 8. This oven is mittent heating at temperatures low enough to v prevent charring have been found not dependable in efiecting sterilizatioh.

The principal object of the invention is a process which will eil'ectco'mplete sterilization of it out any deleteriouseilect on the substance itself. A further objectis a' process which is particumedicinal substance "oilow'meltin'gpoint withlarly adapted for the-sterilization and sealing V of single pellets inindividuai containersor ampuls. Y Other-objects and advantages appear hereinafter.

The invention consistsin placing in the bottom of a test tube, a sterilizing agent non-reactive with the pellet to be, sterilized and having the capacity of sublimation at a temperature low enough to have no harmful eflect on the medicinal pellet, placing a pledget of cotton or the like above said sterilizing material, placing the medlcinal pellet on said pledget, heating the test tube to completely gasiiy the sterilizing material and drive oil the resulting gas and then sealing oil the open end of the test tube. The invention further consists in the process and in the sequence of operations hereinafter described and claimed.

In the drawing, Fig. l is a diagrammatic sectional view of a iurnace and a plurality of test tubes arranged to practice my invention, a

Fig. 2 is an enlarged sectional view oi .a test tube with the several materials in place'iust beiore the construction of the tube near the upper end, a

Fig. 3 is an enlarged sectional view oi a test tube alter constriction; and

Fig. 4 is an enlarged sectional view of the completed ampul after the sterilizing operation.

In the bottom oi a test tube I of thin-walled soft glass. say about three inches long by threeeighths inch in diameter. is placed a suitable quantity, say about fifteen milligrams, of powdered paraiormaldehyde 2. Above the paraheated to a temperature (about sixty. degrees centigrade) sufllcient to slowly vaporize the paraformaldehyde, which sublimes, that is, passes I from the solid directly to the gaseous state with. out intermediate liquefaction. The heating is continued for such time, usually about twentyfour hours; as is required to drive oh the formaldehyde so that no formaldehyde odor is perceptible at thetop oi the tubes; Each tube is then promptly sealed oil,- as by a gas flame, at the constricted upper-end.- Thecotton pledgets"permit the P8 886 and escape of the gasified iorm- .aldehyde. The upper pledget prevents recontamination of the pellet during the slight intervalbeiore the end of the tube is sealed off.

Each sealed tube obviously constitutes 9. hersterile pellet ready for use. The process is particularly applicable to pellets which are used individually, as pellets used for subcutaneous implantation in human subjects.

The detailsabove given are for thepurpose oi illustration and subject to wide variation. The

size 0! the opening at the end of the test tube obviously need be suillcient only to permit insertion of the sterilizing material,- the cotton pledgets and'the pellet to be sterilized. While 'the process has been described in connection with the sterilization of pellets of diethylstilbestrol dipropionate by means of paraformaldehyde, the

. process is applicable to the sterilization of other medicinal pellets and other sterilizing agents may be used, particularly those agents having the property or sublimation. It is essential that the sterilizing agent selected be not reactive with the material being sterilized and it is highly advantageous that it have the property oi sublimation.

What I claim is: l. The process oi sterilizing a medicinal pellet, which comprises placing in the bottom of a test tube a sterilizing agent non-reactive with said medicinal-pellet, placing a cotton pledget above said sterilizing went. placing amodlcinal pellet andthen sealing the end or the tube.

sterilizing agent, placing a-medicinal'pellet on 4 said pledget. heating the tub to completely gasify the sterilizing agent and drive oil the gas and then sealing the end of the tube. Y a

3. The process t sterilizing ame dicinal'pel let, which comprises placing in the bottom of a, test tubea sterilizing agent having the property of sublimation and non-reactive with said'medicinal pellet, placing a cotton pledget above said sterilizing agent, placing. a medicinal pellet on said pledget, placing a cotton pledget in said tube above said pellet, heating the tube to complete- .ly gasify the sterllizing gent and drivev ofi thegas and 'thensealing' the end pi-thetube.

4. 'The process of sterilizing-a medicinal pel- "let, which comprises placlng in the bottom of a test' tube a sterilizing agent having the property 'oisublimation and-non-reactive with said medicinal' pellet, -pla cii ga cotton pledget above said sterilizing a ent, placing a medicinal pellet on said pledget, placing a cotton pledget in said tube above said pellet, constricting'the tube above said upper pledget, heating ,the-tube to completely gasify the sterilizing agent anddrive' off the gas 5. The pr of sterllizing'a pelletof diethylstilbestroidipropionate, which comprises placing powdered paraiormahieliydeinthe bottom of a test tube, placinga cotton pledget, above said paraformaldehyde,-.placing said pellet .on said pledget, heating the tocompletely gasify theIparaformaldehydeand drive ,oiithe gasand then sealing-theend of thetube. v.

.6. The process of sterilizinaapellet oi diethylstilbestrof-'dipropionate; which comprises placingipowdered parai'orinaldelwde in the bottom of a test tube, placing acotton pledget above said paraiormaldehyde, placing sald..pe11et on said pledget, placing acottonpledget in said tube above said pellet, heating the tube to completely gasify the paraformaldehyde and drive all the gas and thensealing the end of the tube.

' The process oi sterilizing a pellet of .diethyl-' stilbestrol dipropionate, which comprises placing powdered paraiormaldehyde in the bottom of a test tube, placing a cotton pledget above said para'formaldehyde, placing said pellet on said pledget, placing a cotton pledget in said tube above said pellet, constricting said tube above said upperpledget. heating the tube to completely' gasiiy theparaiormaldehyde and drive off the gas and then sealing the end of the tube. 1o 8. The process of sterilizing a medicinal pellet,w hich comprises placing in the bottom of a test tubei-ia sterilizing agent non-reactive with said medicinal pellet, placing a cotton pledget 4 above said sterilizing agent, placing a medicinal 15 pellet on said pledget. heating the tube to a temf pe'rature insufllcient to sterilize said pellet but high enough to completely gasify the sterilizing agent and drive oil the gas and then sealing the .end of thetube.

9; The process of sterilizinga medicinal pellet, which-comprises placing in the bottom of .a test tube -'a sterilizing agent having the property of sublimation andhon reactive' with said medicinal pellet, placing'a cotton pledget'ab'ovesaid sterilizing agent. placing aj medicinal pellet on said pledget, heating the tube to'a temperature x-in ufllcient-to sterilize said pellet'but high enough to completely gasifythe'sterilizing agent and drive ofi the'gasandthe'nsealing thejend oi the a 10. The processor sterilizing'a'pellet of diethylstilbestrol dipropionate, whichicomprises' placing .powdered paraiormaldehyde:inthebottom of a test. tube,placing a cotton pledget above said paraiormaldehyde; placing said pellet on "said pledget, heating the tube to 'a temperature insuillcient to sterilize said pelletbu't high enough to completely gasiiy the paraiormaldehyde and drive oil? the gasand then sealing the end of the tube.

40 -11. The processor-sterilizing a' pellet of diethylstilbestrol -dipropionate, which comprises placing powdered paraformaldehyde 'in' the' botto'mof a test tube, placinga cotton pledget above said paraformaldehyde, placing said pellet on said pledget, placinga cotton pledget in said tubeabove said pellet; heating the tube to a temperature insuillcient to sterilize said pellet but high enough to completely gasiiy the paraiormaldehyde and drive oif the gas and then 50 sealing the end or the tube.

" ROBERT E. MULLIGAN.

g .cizhmmd4m'op-cdmchofi. 7 1 i H September 21,1915. Fj oBERTQE. numczgmfl It is he r eby' o ert 1415a arbor appeai- 1n tfie printed specification.. p1 fliepboyg hunbered. .pat ent requiring pogrection aa follows: Page 1, first that the sWQ-myconfozmxtpthp recbrq or the casein:hegmt pmnce.

, Jenivqn Ar sdaid, Acting commissioner of Patents 

